High-pressure-steam system



June 3o, 1925. 1,544,338

A. M. NYGREN HIGH PRESSURE STEAM SYSTEM BY KVM; QW; 1M .f XMI' ATTORNEY s June 30, 1925. 1,544,338

A. M. NYGREN HIGH PRESSURE STEAM SYS/TEM Patented June 30, 1925.

ALFRED M. NY-GRENJ' FREEPORT, YORK'.

HIGH-BRESSURE-S'BEAM SYSTEM.

Application filed Marci; 17, 1-925. serialk ugo. 16,211.

Twill, whom t may oeiicem;

Beit known that I, ALFRED, NreiisN,

citizen of the United South Ocean; Avenue, the eouptii of liessen', A lieve invented eeirtein riep 'aridi useful leipiovements in High-Pressiire-Steem- Sys tems;x find.` 1,. de, hereby declare the following to besa. full., clear, andv exept desorptioii of the; invention, .suoli es Will* enable others skilled in the art to Wliilclfiv it.1,ppe.it;iius to Ineke and use theisame.. i y

*The Lpresent iriveutien relgites to, the @rt of pressure steam hea. t`111guncl @uns partiularly tQ, reducey the Wearon, the vulve-s and valve seats` oi the, traps with which steam heated fixturesJ are Ordinarily equippedi. My inventioi1 oompiisese new .groupingof old aiid stemi-ei'ii, eppfiiietus, 'toe-ether with anewuiethed oi operation whereby a iieuiiesiiltis etteiiied,- il

My improved system has A withpetitulai refe-renee toi-:the iifoeds of hotels` hospitals, eiitll otheri institutions Where the. maintenenee of high pressure Stes-iii trips, lies.-pioved tpoiihleseme arid. espenswe.iv However, my invention. is ees pablo of e, wide variety of psesiii ,inpi'eesips the reliability su@ sleoieelsing;i the. Miei-n teuenteeostin eeieetveiiety of stesso, literate.

States1 residiiug et 81 Eieepert, Ly L, iii

ing systems having piped returns arilx epee.- etipg et sores-lied f-higlipiessures-WBY high pressure steeipX es, that eiipressipn is iises in this epplioetioii, l ineen steam hava, pressure upwardly of, about 20 lbsfper. Square' iiioh, in. ooiitr'zidis-tiiietoii to low Pressure steam heating Where'ithe psessure isordinarily below @peut 5 lbs.w per square inch.v

invention will beeome olesr frein the, .follow ing detailed desoriptien teken; in conjunction with. the, eeeompeiiying drawings wherein- Eig.; 1. a diegpemnietio ifepieseiitetipn ot e row of hotel kitchen -liiitiiifesepeieting in eeiifoirmity with mypieseiit pmeess;

Fie"- Zfis e diegiemmetio illustration of e modiieetien. of .the invention. i

lt iseoiiimon 'preetiee iii hotel kitoheps to heet soup kettlee,` y Vegetable --beilem Coffee u iriisaeiid the, like, with live steam at a, piiesfA suiepf @peut stilles- -pei squaie inerti In osier tezpresuele tor vthe .essuie pteoutlsiiseil Seite of New lorli.,A

.devisedvv The elijeets and edventges et. the present Water eiiol to permit the eiitteiiee eed eiiit of zur,` such Cooking devices must Bre,- Vldell With :i trap out of the 094:51 densed Water may escape enel through which agir may enter when the stinini supply is. eut ofi.l With pressures ask high :is-1 0 ibs. per. square inch the vulve in the trap must closely adjusted and must have :i srgiall exit orifice. This causes e very high, velgityfor the Water, air Or steam, on a, mixture. Qi' the three, and a resultant,A repigiwvezu: of the valve and its, seat, i The piegieseiYe,1 @ewige in they exit orifice under the erpplng aetieii of these, fluids Hughes; it ueeessiiry to queritly adjustthe setting o eige/,h trap,A L practice that is not only expeusive, but :ilse is a. source of great uuuQya-uee iu -npliiote'l kitchen, The valve seits.V ure theru selvesT eXpeiisive, epd tlie iieed. foi ire-leest) ice# placement is likely to ieteifiept, kitelieii .sew ice et :in inopportuue i Aeoordiiig yto the presentieveiitioii. the pressure of the live steam used fer. i,ieggtinjg. iti-iii .leige part ooiiiiteiflieleiioeti by sie pliessiire in the return. pipe with e tliilelepoe et; say 5 lbs. per square ineh betweceu the twoA As e result, the pressure diep fit..v the tuts trap is1 so smell, theft the valve ef the tizep not. pe eloselyediiistei tov its Sees-emi the velopity of the pessiiie weten steam will riet be high enough,toy seizigusgy; erode the metal. of. tlie'velve Qivelve seit- In the preferred einbpdiiiieet oi mi iiiveptigri autom-eti@ ineens are provigl'etll fop-img' 1:1-, taining e pressure of eir the return pige S0 thatl its pressure will be luelovv that o f tue live steam by e ieletivelyfiised eieoiiiit, seit 5. lbs. per square inch, :irrespeeti-ve Ote-uy veiietion iii the steer-i1 pressure iI-ieiieiil i@ normal. o-peifitouy y For puiposee of illiistietioii, l ipill de seribeiiiy invention Yes applied; te sgroup et kitchen fixtures, suoli es; seep ketties., erbitreiily .seleetiiie e 4Q lhs-i steeiii pressure, se representing s soepel eetl ,ty-peel velue enti erbitrferilyseleetipg 5 lbs pressure pei? severe inch as the' desired difereiiceviu pres re between the live steam sindV theliepk sure lef the return or d rip pipes.; It will be understood that muehrhigiier piessiiifes eey be deelt with and. tliet the ieveiitieii is not oiily useful iii hotel kitelieiiefbiit oep lie applied tothe steiilieeisoi hespitels, emi to e ese/et veiiety ei equipee-pt Where sheep cal or physical changes are being wrought through the application of heat from steam.

In Fig. high pressure steam fixtures, suchvasthe soup kettles 1, 2, 3, 4 and 5 are supplied with live steam at 4() lbs. pressure from a main 6. Each ixture is equipped with a control valve 7 to admit or exclude steam from main 6. Each fixture is also equipped with a trap or drip valve 8 of a thermostatic variety to permit 'escape' of air and Water, but to retard as far as is feasible the escape of live steam. Each of these traps 8 discharges into a drip pipe or return line 9. The extreme outer end of steam main 6 may likewise be provided with a trap 10 discharging into return line 9 which in turn is connected with return line 11.

Steam for heating the fixtures above described may be obtained from a boiler header at 100 lbs. pressure through main 12 which is equipped witha hand valve 13. Between'valveV 13 and main 6 is an automatic reducing valve 14 of known construction, preferably of the spring pressed diaphragm type with an air pipe 15 connecting drip pipe 11 with the air space above the diaphragm 16 of the valve, there being a steam connection 17 from pipe 6 to the opposing side of the diaphragm. This diaphragmpressure-reducing valve is preferably set to maintain a lsteam pressure in main 6 about 5 lbs. above that of the air in the return line ,11. Y

Under some circumstances it vis advisable to equip the out-going stretch of pipe 6 with a trap 18and a return drip line 19, as shown in the drawing.

AAir at an appropriate pressure may be obtained in many ways, but according vto the drawing, is obtained from an air compressor 20 driven by an electric motor 21' and equipped in knownmanner with a pressure regulator to shut ofi' at 35 lbs'. pressure. The air is delivered from the vcompressor through 'al pipe 22 into the upper side of a high pressure water tank 23. Drip pipes 11l and A19k also connect with'the upper side of that tank Ithrough an intake'pipe 24. The tank is also equipped with an automatic air relief valve 25, and a valve controlled by-pass 26, both communicating with an air relief line 27 :which discharges into :the atmosphere..

The high water line in tank 23 may be as indicated in the drawing. l"The level of the water may befloa-t controlled in vusual man# ner and tank 23 is equipped withawater discharge pipe 28 through which hot water accumulating in the tank from the steam dripp'ings may be fed to the feed water heater ofthe boiler plant, or may be delivered to astorageta'nlQopen to the atmos-A phere andsuit'a'blyV elevated, or i may be taken off through'f'a spigot," or` through a bucket trap of vusual construction. '.[n'asil much as only water is to be handled through pipe 28, the task of drawing it off, even at 35 lbs. pressure is not va serious one.

With apparatus of standard construction arranged and connected as above described, the operation ofthe system is essentially as follows:

With valve 13 closed and with no steam in the. kitchen fixtures, air compressor 20 will deliver air through pipe 22, tank 23, drip pipes 11 and 19, and the pipes connected therewith, into the steam space of the kitchen fixtures until there is attained an air pressure therein of approximately 35 lbs. per square inch. Valve 14 under these conditions will be wide o-pen and ready to pass steam to the kitchen'ixtures. Valve 13 can then be opened to admit live steam into pipe 6 by way vof the pressure reducing valve 14. This steam on entering the kitchen fixtures will force out the air and raise the temperature of the fixtures. Such water of condensation as may form will pass out with the air, orsubsequently thereto, but the exit of air and of water will not occur vuntil the pressure of live steam'in the fixtures is somewhat; higher than 35 lbs. per square inch. The steam pressure cannot be much higher than 35 lbs. because of the automatic throttling of theair-balanced reducing valve 14. An excess of 5 lbs-in steam pressure over air pressure will be suicient to readily clear the kitchen fixtures of air and water without violeneefto the traps Vor exit valves. The water so deliveredl through the traps 8 will pass down through return lines 9 and 11, into tank 23, and vfrom there can be drawn off, either automatically orl by hand, through pipe 28. If desired, the steam pressure may be built up prior to or simultaneously with the building up of air pressure.

-When the system 1s in normal operation,v

the air pressure is automatically held at approximately 35 lbs.` Vthrough automatic starting and stopping of condenser v20, safeguarded by the automatic air relief valve 25. The pressure reducing valve 14, lwill serve to keep the steam pressure atabout. 40 lbs. regardless of wide variations inthe boiler pressure in pipe 12.`v Anychange in air pressure will be accompanied'bya corresponding change in steam pressure even to the extent of entirely cutting off the steam at valve 14 at failure of the" air.

As above explained,the automatic return traps 8 and 18 need notbe closely adjusted, and are not subjected to the wear of fluids at high velocity, and in materials and l' construction, and cost of maintenance, are not essentially different from the low pressure traps so very commonly used onthe'returns of radiators utilized for domestich'eating.

'In the system above described, the air pressure is maintained substantially Lc011- messes stanlt at say 36" lbs. and the stesan from a keiler atv much higher messer-eg say 1100 lbsl is autocally ,reduced to a pressure not that of the air by more than about 5 lbs. In Fig. 2, on the contrary, the kitchen fixtures, or that class of equipment of which kitchen fixtures are representative, receive steam directly from the boiler at whatever the boiler pressure may be, and the wir pressure is automatically regulated so that it will at all times stay at about 5 lbs. below that of the steam.

In Fig. 2, the fixtures' 29, 30, 31 and 32 are each provided with a hand valve 33 and receive live steam through mains 34 and 34', which communicate through a hand valve 35 with the steam supp-ly main 34 wherein the pressure is that desired for the fixtures, it being understood that the boiler' pressure will not be unsuited to the mechanical strength of the fixtures. A thermostatic trap 36 drain's pipe 34 into drip line 36', and similar automatic traps 37 and 38 drain the fixtures into the return pipes 39 and 40 which empty into tank 41. From tank 41 the Water can be withdrawn by hand thrcugh spigot 42, or can be discharged by way of pipe 43 into a feed water heater, a storage tank, at bucket trap, or the like, means being used for effecting the discharging automaticlly if desired as will be readily under- Air for use in counter-balancing the steam is supplied through pipe 44 at a pressure comparable to the maximum steam pressure to be anticipated in pipe 34". In other words, the air pressure at 44 is substantially above that desired in the return lines. Interposed in pipe 44 is a pressure reducing valve 45, like that heretofore described, having a steam chamber below its diaphragm 46 in communication through pipe 47 with steam main 34 and having an air or water chamber above that diaphragm and communicating through pipe 48 with drip line 36. It. is the function of this device to automatically admit air to the return lines when the pressure difference between the steam and the return lines exceeds a certain desired value, say 5 lbs. per square inch. In other words. this device will increase the air pressure as the steam pressure goes up, and is calibrated to keep the air pressure about 5 lbs. below the steam pressure. To take care of the conditions resulting from a falling steam pressure. there is provided a second pressure reducing valve 49 interposed in an air discharge line 50 which communicates at one end with drip line 40, and at its other end discharges into the atmosphere. The chamber below its spring-balanced diaphragm 51 communicates through pipe 52 with air pipe 50, and the chamber above its diaphragm communicates through pipe 53 with steam line 34. As thus arranged, this device acts to automatically discharge air from the return or drip line when the pressure difference between the steam and the return line' is less than a certain desired value, say 5 lbs. per square inch.

ly the grouping of standard apparatus in the manner above described, steam at boiler pressure may be used to heat the fixtures, and the counter-balancing air pressure will fluctuate up or down in such a way as to keep the air pressure in the return lines just enough lower than the active steam pressure in the fixtures to permit ready discharge of air or water from the fixtures without excessive velocity or wear at the automatic drip valves or traps of the fixtures.

Ars above indicated, I have used the term fixtures herein as generic to kitchen kettles'. hospital stcrilizers, heating coils of evaporators. high pressure steam mains` and other like apparatus and equipment, und. in general, steam consuming apparatus operable on high pressure steam, in contradistinction to the low pressure heaters suited to exposed heating in domestic installations.

I am aware that many changes can bc made in details of the several elements and in the grouping of those elements and in their mode of operation, without departing from the spirit of my invention as defined by the appended claims.

I claim:

1. The combination of a heating fixture having a trap with a relatively large orifice. means for supplying high pressure steam to said fixture. and means for connterbalancing said steam at said trap with air at a slightly lo'wer pressure, substantially as described.

2. The combination of a heating fixture having a trap with a relatively large orifice, a drip pipe leading from said trap, a water tank into which said pipe discharges, means for supplying steam to said fixture, and means for maintaining an air pressure in said tank and drip pipe slightly below the steam pressure at said trap.

3. The combination of a heating fixture having a thermostatically trapped outlet with a relatively large orifice, a drip pipe leading therefrom, a water tank into which said drip pipe discharges, means for auto-' matically withdrawing water from said tank, means for supplying high pressure steam to said heating fixture, and means for maintaining an air pressure 1n said drip pipe approximately 5 lbs. below the steam pressure in said fixture, substantially as described.

4. The combination of a heating fixture having a discharge trap with a relatively large orifice, a drip pipe leading therefrom, means for supplying high pressure steam to said heating fixture at a pressure which is substantially constant. and means for supplying air to said drip pipe at a pressure which is substantially constant and which is about 5 lbs. below the pressure of the steam in the heating fixture.

5. The combination of a heating fixture having a discharge trap, a drip pipe leading therefrom, means for delivering compressed air to said drip pipe at substantially constant pressure, means for delivering high pressure steam to said fixture, and automatic means for regulating the steam in said fixture to a pressure slightly higher than the pressure of the air in said drip pipe.

6. In a system of' the character described, the combination of a heating fixture having a thermostatic trap with a relatively large discharge orifice, a drip pipe connected therewith, a water tank into which said drip pipe may discharge. an air compressor automatically regulated to normally deliver air to said tank and drip pipe at a constant pressure, means for delivering high pressure steam to said fixture, and means for automatically regulating the pressure of the steam in the fixture to a value about 5 lbs. above the pressure of air in said tank and drip pipe.

7. The method of reducing wear in the trap of a fixture heated by high pressure steam which consists in counter-balancing the steam on one side of said trap with air on the other side of' said trap, said air being at a pressure slightly below that of the steam` substantially as described.

8. The method of reducing the wear and maintenance cost on the drip trap of a fixture heated by high pressure steam which con sists in setting the trap to a relatively wide orifice and partly counter-balancing the steam on one side of said trap with air on the other side thereof, the respective pressures of steam and air being maintained relatively close to one another, substantially as described.

9. The method of reducing the wear and maintenance cost on the trap of a fixture heated with steam at high pressure which consists in maintaining a substantially constant air pressure on the exit side of said trap and automatically correlating the pressure of steam on the other side of said trap to a value about 5 lbs. higher.

10. The method of operating a high pressure steam heated fixture having a steam trap, and a drip pipe connected therewith, which consists in adjusting said trap to a relatively large discharge orifice, maintaining a substantially constant air pressure in said drip pipe, and automatically regulating the supply of' steam to said fixture so that the steam pressure on one side of said trap will be about 5 lbs. greater than the air pressure on the other side of said trap.

11. The method of operating at high steam pressure a heating fixture having a steam trap communicating with a water tank through a drip pipe, which consist-s in maintaining a substantially constant air pressure in said tank and pipe, supplying high pressure steam to said fixture, and automatically regulating said supply of steam to said fixture at a pressure near enough to the pressure of the air in said drip pipe to permit a relatively wide opening of said trap, substantially as described.

In testimony whereof I affix my signature.

ALFRED M. NYGREN. 

